Vertical hall effect sensor and a brushless electric motor having a vertical hall effect sensor

Abstract

A vertical Hall sensor includes a semiconductor crystal with three or more arm sections that are arranged at a uniform angle distance to each other. A central electrode and external current electrodes are arranged on the surface of the sensor, and a plurality of Hall voltage contacts is arranged therebetween. The semiconductor crystal is thick enough for a current flow to pass between the electrodes in each arm section of the semiconductor crystal, whereby the current flow produces several sensitivities in the Hall sensor corresponding to the number of arm sections with a correspondingly predefined angular dependency for a magnetic field that is directed in a parallel position with respect to the surface. The Hall voltages, which can be produced using one such multi-arm vertical Hall sensor, can be used in a reinforced and direct manner as an output signal for an electric motor.

What is claimed is:  
     
       1. A vertical Hall effect sensor, comprising: 
       a semiconductor crystal having a pair of current electrodes arranged on a surface thereof and having a Hall effect voltage contact arranged between the pair of current electrodes,  
       wherein the semiconductor crystal has sufficient thickness to allow a current flow between the pair of current electrodes in the semiconductor crystal, which current flow makes the Hall effect sensor sensitive to a magnetic field aligned parallel to the surface,  
       wherein the Hall effect sensor has at least three arm sections which are arranged at equal angular intervals from one another and which run together in a central section,  
       wherein each of the arm sections has an outer current electrode which is arranged opposite a central inner current electrode in the central section, with the outer current electrodes in each case forming the pair of current electrodes,  
       wherein a Hall effect voltage contact is arranged between the respective outer current electrodes and the central inner current electrodes to allow a current flow between the outer current electrodes in each of the arm sections of the semiconductor crystal, which current flow produces a plurality of output signals from the Hall effect sensor for a magnetic field aligned parallel to the surface corresponding to the number of arm sections and with a predetermined angle dependency, and  
       wherein the three arm sections are arranged at an angle of 120° to one another.  
     
     
       2. The vertical Hall effect sensor as claimed in  claim 1 , wherein a buried layer is provided in each of the arm sections of the semiconductor crystal for producing the current flow. 
     
     
       3. The vertical Hall effect sensor as claimed in  claim 1 , wherein the outer current electrodes are electrically conductive strips, and wherein the Hall effect voltage contacts are electrically conductive strips arranged parallel to the outer current electrodes. 
     
     
       4. The vertical Hall effect sensor as claimed in  claim 1 , wherein a buried layer is provided in each of the arm sections of the semiconductor crystal for producing the current flow. 
     
     
       5. The vertical Hall effect sensor as claimed in  claim 1 , wherein the outer current electrodes are electrically conductive strips, and wherein the Hall effect voltage contacts are electrically conductive strips arranged parallel to the outer current electrodes. 
     
     
       6. The vertical Hall effect sensor as claimed in  claim 2 , wherein the outer current electrodes are electrically conductive strips, and wherein the Hall effect voltage contacts are electrically conductive strips arranged parallel to the outer current electrodes. 
     
     
       7. A vertical Hall effect sensor, comprising: 
       a semiconductor crystal having a pair of current electrodes arranged on a surface thereof and having a Hall effect voltage contact arranged between the pair of current electrodes,  
       wherein the semiconductor crystal has sufficient thickness to allow a current flow between the pair of current electrodes in the semiconductor crystal, which current flow makes the Hall effect sensor sensitive to a magnetic field aligned parallel to the surface,  
       wherein the Hall effect sensor has at least five arm sections which are arranged at equal angular intervals from one another and which run together in a central section,  
       wherein each of the arm sections has an outer current electrode which is arranged opposite a central inner current electrode in the central section, with the outer current electrodes in each case forming the pair of current electrodes,  
       wherein a Hall effect voltage contact is arranged between the respective outer current electrodes and the central inner current electrodes to allow a current flow between the outer current electrodes in each of the arm sections of the semiconductor crystal, which current flow produces a plurality of output signals from the Hall effect sensor for a magnetic field aligned parallel to the surface corresponding to the number of arm sections and with a predetermined angle dependency, and  
       wherein the five arm sections are arranged at an angle of 72° to one another.